Costs of treatment affect compliance to specific subcutaneous immunotherapy

Specific subcutaneous immunotherapy (SCIT) is cost-effective; however its economical burden can lead to non-adherence. We aimed to identify the reported reasons, patient's personal or socio-demographic characteristics and SCIT-related factors associated with non-adherence to SCIT.

This is a cross-sectional, observational study held in a Portuguese University Hospital. All records from patients starting SCIT in the last 4 years were reviewed in July 2011. Those without registry of SCIT administration in the previous 3 months were included (n = 181). A telephonic survey was performed and 56 were confirmed as non-adherent; reasons for discontinuation were assessed. Univariate and multiple logistic regression models were developed using characteristics previously described as being associated with non-adhesion.

Economical burden of SCIT was the most important factor leading to treatment discontinuation (40%). In the univariate analysis, presence of family history of allergic disease treated with immunotherapy was associated with decreased OR of non-adherence to SCIT (OR [95%CI] = 0.31 [0.11- 0.88]). In the multiple logistic regression model, none of the factors was significantly associated with non-adherence.

Adherence is influenced by economic factors. More attention should be given to the impact of economic changes in allergic patient's treatment.